title: Rapid determination of total conjugated linoleic acid content in select Canadian cheeses by (1)h NMR spectroscopy.
abstract: The application of (1)H nuclear magnetic resonance (NMR) spectroscopy to the measurement of conjugated linoleic acid (CLA) content in the lipid fraction of dairy products is both a novel and inviting alternative to traditional methods such as gas chromatography (GC), which can require time-consuming sample derivatization. In this work, a newly developed, rapid, and reliable lipid extraction protocol was combined with simple, nondestructive (1)H NMR spectroscopic analysis to measure the total CLA content in CLA standards and in various Canadian cheeses from conventional, organic, and grass-fed dairy sources. The total CLA concentrations (mg/g cheese) obtained using these new extraction and analysis methods were consistent with amounts found using the modified Folch extraction and GC analysis (correlation coefficient of 0.948). Results showed that cheeses from exclusively grass-fed dairy cows were significantly higher in total CLA content than either conventional or organic cheese.
authors.affiliation: Department of Physical Sciences and ‡Department of Natural Resource Science, Thompson Rivers University , Kamloops, British Columbia V2C 0C8, Canada.
authors.forename: Dipesh
authors.initials: D
authors.lastname: Prema
authors.forename: Jessica L
authors.initials: JL
authors.lastname: Pilfold
authors.forename: Jessica
authors.initials: J
authors.lastname: Krauchi
authors.forename: John S
authors.initials: JS
authors.lastname: Church
authors.forename: Kingsley K
authors.initials: KK
authors.lastname: Donkor
authors.forename: Bruno
authors.initials: B
authors.lastname: Cinel
mesh_terms: D000818:Animals; D002170:Canada; D002417:Cattle; D002611:Cheese / Q000032:analysis*; D002849:Chromatography, Gas; D044243:Linoleic Acids, Conjugated / Q000032:analysis*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008892:Milk / Q000737:chemistry
chemical_list: D044243:Linoleic Acids, Conjugated